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AltOS 1.6.3 —

AltOS is the core of the software
for all of the Altus Metrum products. It
consists of firmware for our cc1111, STM32L151, STMF042, LPC11U14 and ATtiny85
based electronics and Java-based ground station software.

Version 1.6.3 adds idle mode to AltosDroid and has bug fixes
for our host software on desktops, laptops an android devices
along with BlueTooth support for Windows.

AltosDroid

Remote reboot. Cause the flight computer to reboot over the
radio link. This provides a method for switching the flight
computer from idle to flight mode without needing to reach
the power switch.

Configurable frequency menu. Change the set of available
frequencies and provide more descriptive names.

AltosDroid bug fixes:

Don't set target location if GPS hasn't locked yet.

Fix saving target states so they can be reloaded when the
application restarts. When the application is shut down and
restarted, all previous target state information will be
restored (including GPS position if available).

Fix crash on some Android devices for offline maps when
changing the map scale or location.

Don't require USB OTG support. This kept the latest
AltosDroid from being offered on devices without USB device
support, although it can work without that just fine using
BlueTooth.

Don't require bluetooth to be enabled. This allows the
application to operate with USB devices or just show old
data without turning on the bluetooth radio.

Recover old tracker positions when restarting
application. This finally allows you to safely stop and
restart the application without losing the last known
location of any tracker.

AltOS is the core of the software
for all of the Altus Metrum products. It
consists of firmware for our cc1111, STM32L151, STMF042, LPC11U14 and ATtiny85
based electronics and Java-based ground station software.

This is a minor release of AltOS, including support for our new
TeleMega v2.0 board, a small selection
of bug fixes and a major update of the documentation

AltOS Firmware — TeleMega v2.0 added

The updated six-channel flight computer, TeleMega v2.0,
has a few changes from the v1.0 design:

CC1200 radio chip instead of the CC1120. Better receive performance
for packet mode, same transmit performance.

TeleLaunchTwo — A Smaller Wireless Launch Controller

I've built a wireless launch control system for NAR and OROC. Those
are both complex systems with a single controller capable of running
hundreds of pads. And, it's also complicated to build, with each board
hand-made by elves in our Portland facility (aka, my office).

A bunch of people have asked for something simpler, but using the same
AES-secured two-way wireless communications link, so I decided to just
build something and see if we couldn't eventually come up with
something useful. I think if there's enough interest, I can get some
boards built for reasonable money.

Here's a picture of the system; you can see the LCO end in a box
behind the pad end sitting on the bench.

Radio Link

Each end has a 35mW 70cm digital transceiver (so, they run in the
440MHz amateur band). These run at 19200 baud with fancy forward error
correction and AES security to keep the link from accidentally (or
maliciously) firing a rocket at the wrong time. Using a bi-directional
link, we also get igniter continuity and remote arming information at
the LCO end.

The LCO Box

In the LCO box, there's a lipo battery to run the device, so it can be
completely stand-alone. It has three switches and a button -- an
arming switch for each of two channels, a power switch and a firing
button. The lipo can be charged by opening up the box and plugging it
into a USB port.

The Pad Box

The pad box will have some cable glands for the battery and each
firing circuit. On top, it will have two switches, a power switch and
an arming switch. The board has two high-power FETs to drive the
igniters. That should be more reliable than using a relay, while also
allowing the board to tolerate a wider range of voltages -- the pad
box can run on anything from 12V to 24V.

The Box

Unlike the OROC and NAR systems, these boards are both designed to fit
inside a specific box, the Hammond 1554E, and use the mounting
standoffs provided. This box is rated at NEMA 4X, which means it's
fairly weather proof. Of course, I have to cut holes in the box, but I
found some NEMA 4X switches, will use cable glands for the pad box
wiring and can use silicone around the BNC connector. The result
should be pretty robust. I also found a pretty solid-seeming BNC
connector, which hooks around the edge of the board and also clips
on to the board.

Safety Features.

There's an arming switch on both ends of the link, and you can't
fire a rocket without having both ends armed. That provides an extra
measure of safety while working near the pad. The pad switch is a
physical interlock between the power supply and the igniters, so even
if the software is hacked or broken, disarming the box means the
igniters won't fire.

The LCO box beeps constantly when either arming switch is selected,
giving you feedback that the system is ready to fire. And you can see
on any LED whether the pad box is also armed.

AltOS 1.6 — TeleDongle v3.0 support and bug fixes

AltOS is the core of the software
for all of the Altus Metrum products. It
consists of firmware for our cc1111, STM32L151, STMF042, LPC11U14 and ATtiny85
based electronics and Java-based ground station software.

This is a major release of AltOS, including support for our new
TeleDongle v3.0 board and a selection
of bug fixes

AltOS Firmware — TeleDongle v3.0 added along with some fixes

Our updated ground station, TeleDongle v3.0,
works just like the original TeleDongle, but is an all-new design:

CC1200 radio chip is about 5dB more sensitive than TeleDongle's CC1111.

LPC11U14 CPU can be reprogrammed over the USB link.

AltOS Bug Fixes

We also fixed a few bugs in the firmware:

Make sure the startup flight computer beeps are
consistent. Sometimes, it was taking long enough to beep out the
battery voltage that the flight computer state was changing in the
middle, causing a bit of confusion.

Change TeleDongle's LED indicators during telemetry
reception. The green LED blinks on successful packet
reception, and the red LED blinks when a packet with an invalid
checksum is received.

The SPI driver used in both TeleDongle v3 and TeleGPS has been
rewritten to avoid locking up under heavy CPU load. If you've got a
TeleGPS board, you'll want to reflash with new firmware.

AltosUI and TeleGPS applications

A few minor new features are in this release

AltosUI can now compute and display tilt angle when graphing eeprom
log data from TeleMega and EasyMega.

The AltosUI tool window is shown when starting with a data
file. This way, when you double-click on a file in the file
manager, you'll get the whole AltosUI interface, rather than just
the graphing window.

At the end of replaying an old log file, stick 'done' in the Age
field so you can tell the recording is over.

Bug Fixes

There are a bunch of minor bug fixes, including the usual collection
of attempts to make stuff behave better on Windows platforms.

Use a different Windows API to discover USB device ids. This works
better on my new HP Windows 7 machine. Maybe it will work better
for other people too?

Look in more places in the Windows registry to try and find the
installed Java version. It appears that the default Java download
from Oracle is a 32-bit version? In any case, that version sticks
its install information in a different spot in the registry.

Fix file associations on Windows when Java isn't installed in the
system root.

Make 'Scan Channels' work better with new AltOS firmware which only
reports device configuration information once ever five seconds.

Altus Metrum's 2014 Black Friday Event

We are pleased to announce that both TeleMetrum and TeleMega will be
back in stock and available for shipment before the end of November.
To celebrate this, any purchase of a TeleMetrum, TeleMega, or EasyMega
board will include, free of charge, one each of our 160, 400, and 850 mAh
Polymer Lithium Ion batteries and a free micro USB cable!

To celebrate NAR's addition of our 1.9 gram recording altimeter, MicroPeak,
to the list of devices approved for use in contests and records, and help
everyone get ready for NARAM 2015's altitude events, purchase 4 MicroPeak
boards and we'll throw in a MicroPeak USB adapter for free!

These deals will be available from 00:00 Friday, 28 November 2014 through
23:59 Monday, 1 December, 2014. Only direct sales through our web store
at http://shop.gag.com are included; no other discounts apply.

Neil Anderson Flies EasyMega to 118k' At BALLS 23

Altus Metrum would like to congratulate Neil Anderson and Steve
Cutonilli on the success the two stage rocket, “A Money Pit”, which
flew on Saturday the 20th of September on an N5800 booster followed by
an N1560 sustainer.

“A Money Pit” used two Altus MetrumEasyMega flight computers in the
sustainer, each one configured to light the sustainer motor and deploy
the drogue and main parachutes.

Safely Staged After a 7 Second Coast

After the booster burned out, the rocket coasted for 7 seconds to 250m/s, at
which point EasyMega was programmed
to light the sustainer. As a back-up, a timer was set to light the
sustainer 8 seconds after the booster burn-out. In both cases, the
sustainer ignition would have been inhibited if the rocket had tilted
more than 20° from vertical. During the coast, the rocket flew from
736m to 3151m, with speed going from 422m/s down to 250m/s.

Apogee Determined by Accelerometer

Above 100k', the MS5607 barometric sensor is out of range. However, as
you can see from the graph, the barometric sensor continued to return
useful data. EasyMega doesn't expect that to work, and automatically
switched to accelerometer-only apogee determination mode.

Because off-vertical flight will under-estimate the time to apogee
when using only an accelerometer, the EasyMega boards were programmed
to wait for 10 seconds after apogee before deploying the drogue
parachute. That turned out to be just about right; the graph shows the
barometric data leveling off right as the apogee charges fired.

Fast Descent in Thin Air

Even with the drogue safely fired at apogee, the descent rate rose to
over 200m/s in the rarefied air of the upper atmosphere. With
increasing air density, the airframe slowed to 30m/s when the main
parachute charge fired at 2000m. The larger main chute slowed the
descent further to about 16m/s for landing.

AltOS 1.5 — EasyMega support, features and bug fixes

AltOS is the core of the software
for all of the Altus Metrum products. It
consists of firmware for our cc1111, STM32L151, LPC11U14 and ATtiny85
based electronics and Java-based ground station software.

This is a major release of AltOS, including support for our new
EasyMega board and a host of new
features and bug fixes

AltOS Firmware — EasyMega added, new features and fixes

Orientation tracking using the gyroscopes (and quaternions, which
are lots of fun!)

Four fully-programmable pyro channels, in addition to the usual
apogee and main channels.

AltOS Changes

We've made a few improvements in the firmware:

The APRS secondary station identifier (SSID) is now
configurable by the user. By default, it is set to the last digit
of the serial number.

Continuity of the four programmable pyro channels on EasyMega and
TeleMega is now indicated via the beeper. Four tones are sent out
after the continuity indication for the apogee and main channels
with high tones indicating continuity and low tones indicating an
open circuit.

Configurable telemetry data rates. You can now select among 38400
(the previous value, and still the default), 9600 or 2400 bps. To
take advantage of this, you'll need to reflash your TeleDongle or
TeleBT.

AltOS Bug Fixes

We also fixed a few bugs in the firmware:

TeleGPS had separate flight logs, one for each time the unit was
turned on. Turning the unit on to test stuff and turning it back
off would consume one of the flight log 'slots' on the board; once
all of the slots were full, no further logging would take
place. Now, TeleGPS appends new data to an existing single log.

Increase the maximum computed altitude from 32767m to
2147483647m. Back when TeleMetrum v1.0 was designed, we never
dreamed we'd be flying to 100k' or more. Now that's surprisingly
common, and so we've increased the size of the altitude data
values to fit modern rocketry needs.

Continuously evaluate pyro firing condition during delay
period. The previous firmware would evaluate the pyro firing
requirements, and once met, would delay by the indicated amount and
then fire the channel. If the conditions had changed state, the
channel would still fire. Now, the conditions are continuously
evaluated during the delay period and if they change state, the
event is suppressed.

Allow negative values in the pyro configuration. Now you can select
a negative speed to indicate a descent rate or a negative
acceleration value to indicate acceleration towards the ground.

AltosUI and TeleGPS — EasyMega support, OS integration and more

The AltosUI and TeleGPS applications have a few changes for this release:

EasyMega support. That was a
simple matter of adapting the existing TeleMega support.

Added icons for our file types, and hooked up the file manager so
that AltosUI, TeleGPS and/or MicroPeak are used to view any of our
data files.

AltOS 1.4.1 — Fix ups for 1.4

AltOS is the core of the software
for all of the Altus Metrum products. It
consists of firmware for our cc1111, STM32L151, LPC11U14 and ATtiny85
based electronics and Java-based ground station software.

This is a minor release of AltOS, incorporating a small handful of
build and install issues. No new features have been added, and the
only firmware change was to make sure that updated TeleMetrum v2.0
firmware is included in this release.

AltOS — TeleMetrum v2.0 firmware included

AltOS version 1.4
shipped without updated firmware for TeleMetrum v2.0. There are a couple of
useful new features and bug fixes in that version, so if you have a
TeleMetrum v2.0 board with older firmware, you should download this
release and update it.

AltosUI and TeleGPS — Signed Windows Drivers, faster maps downloading

We finally figured out how to get our Windows drivers signed making it
easier for Windows 7 and 8 users to install our software and use our
devices.

Also for Windows users, we've fixed the Java version detection so
that if you have Java 8 already installed, AltOS and TeleGPS won't try
to download Java 7 and install that. We also fixed the Java download
path so that if you have no Java installed, we'll download a working
version of Java 6 instead of using an invalid Java 7 download URL.

Finally, for everyone, we fixed maps downloading to use the authorized
Google API key method for getting map tiles. This makes map
downloading faster and more reliable.

TeleGPS Battery Life

I charged up one of the
"160mAh" batteries that we sell.
(The ones we've got now are labeled 200mAh; the 160mAh rating is
something like a minimum that we expect to be able to ever get at that size.)

I connected the battery to a TeleGPS board, hooked up a telemetry monitoring
setup on my laptop and set the device in the window of my office. This
let me watch the battery voltage through the day without interrupting
my other work. Of course, because the telemetry was logged to a file,
I've now got a complete plot of the voltage data:

It looks like a pretty typical lithium polymer discharge graph;
slightly faster drop from the 4.1V full charge voltage down to about
3.9V, then a gradual drop to 3.65 at which point it starts to dive as
the battery is nearly discharged.

Because we run the electronics at 3.3V, and the LDO has a dropout of
about 100mV, it's best if the battery stays above 3.4V. That occurred
at around 21500 seconds of run time, or almost exactly six hours.

We also have an
"850mAh" battery
in the shop; I'd expect that to last a bit more than four times as
long, or about a day. Maybe I'll get bored enough at some point to
hook one up and verify that guess.

AltOS 1.4 — TeleGPS support, features and bug fixes

AltOS is the core of the software
for all of the Altus Metrum products. It
consists of firmware for our cc1111, STM32L151, LPC11U14 and ATtiny85
based electronics and Java-based ground station software.

This is a major release of AltOS, including support for our new
TeleGPS board and a host of new
features and bug fixes

AltOS Firmware — TeleGPS added, new features and fixes

Our new tracker, TeleGPS,
works quite differently than a flight computer

For TeleMega, we've made the
firing time for the additional pyro channels (A-D) configurable, in
case the default (50ms) isn't long enough.

AltOS Beeping Changes

The three-beep startup tones have been replaced with a report of the
current battery voltage. This is nice on all of the board, but
particularly useful with EasyMini which doesn't have the benefit of
telemetry reporting its state.

We also changed the other state tones to "Farnsworth" spacing. This
makes them all faster, and easier to distinguish from the numeric
reports of voltage and altitude.

Finally, we've added the ability to change the frequency of the beeper
tones. This is nice when you have two Altus Metrum flight computers in
the same ebay and want to be able to tell the beeps apart.

AltOS Bug Fixes

Fixed a bug which prevented you from using
TeleMega's extra pyro channel
'Flight State After' configuration value.

AltOS 1.3.2 on TeleMetrum v2.0 and TeleMega would reset the flight
number to 2 after erasing flights; that's been fixed.

AltosUI — New Maps, igniter tab and a few fixes

With TeleGPS tracks now
potentially ranging over a much wider area than a typical rocket
flight, the Maps interface has been updated to include zooming and
multiple map styles. It also now uses less memory, which should make
it work on a wider range of systems.

For TeleMega, we've added an
'Igniter' tab to the flight monitor interface so you can check
voltages on the extra pyro channels before pushing the button.

We're hoping that the new Maps interface will load and run on machines
with limited memory for Java applications; please let us know if this
changes anything for you.

TeleGPS — All new application just for TeleGPS

While TeleGPS shares the same
telemetry and data logging capabilities as all of the Altus Metrum
flight computers, its use as a tracker is expected to be both broader
and simpler than the rocketry-specific systems. We've build a custom
TeleGPS application that incorporates the mapping and data
visualization aspects of AltosUI, but eliminates all of the
rocketry-specific flight state tracking.